package com.example.myapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
    private Button btnQuery;
    private Button btnAdd;
    private TextView txtResult;
    private EditText edtNo;
    private EditText edtName;
    private EditText edtAge;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    txtResult=findViewById(R.id.txtResult);
    btnQuery=findViewById(R.id.btn_query);
        btnQuery.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Uri uri = Uri.parse("content://com.gdcp.student/student");
            Cursor cursor = getContentResolver().query(uri, null, null, null, null);
            if(cursor != null && cursor.getCount() > 0){
                StringBuffer buffer = new StringBuffer();
                for(cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()){
                    String stuno = cursor.getString(0);
                    String name = cursor.getString(1);
                    int age = cursor.getInt(2);
                    buffer.append(stuno).append("  ").append(name).append("  ").append(age).append("\n");
                }

                txtResult.setText(buffer);
            }else{
                txtResult.setText("行数为0");
            }
        }
    });

    edtAge=findViewById(R.id.edtAge);
    edtName=findViewById(R.id.edtName);
    edtNo=findViewById(R.id.edtNo);
    btnAdd=findViewById(R.id.btn_add);
        btnAdd.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            String no=edtNo.getText().toString();
            String name=edtName.getText().toString();
            int age=Integer.parseInt(edtAge.getText().toString());
            Uri uri = Uri.parse("content://com.gdcp.student/student");
            ContentValues values = new ContentValues();
            values.put("stuno", no);
            values.put("name", name);
            values.put("age", age);
            getContentResolver().insert(uri, values);
        }
    });
}
}
